Apparatus for feeding lifts of sheets without marking same

ABSTRACT

A sheet magazine containing limp sheets, cover sheets or carbon sheets avoids stabber damage and carbon smudging of conventional feeds by the use of a sharp pointed, small diameter segregation needle cooperable with but independently mounted relative to a pressure clamp member and a hold back finger member. The needle reciprocates parallel to the plane of the sheets on a movable member at the magazine gateway to pierce into the stack between adjacent sheets without damaging the sheets. The movable member then moves the needle away from the stack to form a separation gap which permits extraction by gripper jaws.

United States Patent Stacy 51 Sept. 12', 1972 [54] APPARATUS FOR FEEDING LIFTS OF [57] ABSTRACT SHEETS WITHOUT MARKING SAME A sheet magazine containing limp sheets, cover sheets I [72] Inventor: Edson H. Stacy, East Baldwin, or carbon sheets avoids stabber damage and carbon Maine smudging of conventional feeds by the use of a sharp [22] Filed: June 21, 1971 pointed, small diameter segregation needle cooperable with but independently mounted relative to a pressure [21] Appl- 154,832 clamp member and a hold back finger member. The needle reciprocates parallel to the plane of the sheets [52] U.S.Cl. ..2l4/8.5 SS, 2l4/8.5 C on a movable member at the magazine gateway to [5 1] Int. Cl ..B65g 59/06 pierce into the stack between adjacent sheets without [58] Field of Search...2l4/8.5 SS, 8.5 A, 8.5 R, 8.5 C damaging the sheets. The movable member then moves the needle away from the stack to form a References Clled separation gap which permits extraction by gripper UNITED STATES PATENTS Jaws- 3,391,806 7/1968 Geis ..2l4/8.5 C 3,608,747 9/1971 Shibata ..2l4/8.S A

Primary Examiner-Gerald M. Forlenza Assistant Examiner-George F. Abraham Attorney-Pearson & Pearson 10 Claims, 9 Drawing Figures l/I/l/l/ I PATENTED E I2 I97? 3.890.476

sum 1 BF 2 INVENTOR. EDSON H. STACY 7 3 ATTORNEYS APPARATUS FOR FEEDING LIFIS OF SHEETS WITHOUT MARKING SAME RELATED APPLICATIONS This application relates to my application Ser. No. 808,724 of Mar. 20, 1969, entitled Automatic Feed for Lifts of Paper, in that a combined stabber gripper is provided in that application which forcibly enters the front of the stack to create a separation gap and then grips and partially withdraws a lift into the nip of rotating pressure rolls which complete the extraction.

FIELD OF THE INVENTION The feeding of individual sheets of self-supporting material can be accomplished by well known means such as a bottom, end, or top feed magazine having a pivoted suction cup or friction rolls for advancing sheets individually and successively out of a magazine gateway onto a paper line, conveyor, registration chain or the like.

Sheet feeding becomes more difiicult when the sheets are limp since they will buckle if frictionally engaged or pushed and even more difficult when it is desired to feed individual and successive lifts of such limp sheets.

In this invention, not only are the lifts made up of limp flimsy sheets, but there may be limp carbon papers interposed in the stack and there may be self-supporting sheets such as notebook covers or pad backers spaced through the stack.

DESCRIPTION OF THE PRIOR ART In US. Pat. No. 3,327,873 to Malamood of June 27, I967, the feeding of limp sheets is accomplished by a combined segregator-separator in the form of a sharp pointed stabber arm having a wedge-shaped lower face for penetrating into the stack and bending each successive lowermost lift away from the stack so that the leading edges may be gripped and extracted by gripper aws.

In my above mentioned co-pending application, Ser. No. 808,724, a combined segregator, separator and gripper jaw member is disclosed, the member having a sharp pointed stabber, wedge-shaped upper face and a gripper so that the stack is forcibly penetrated, the stack lifted by the wedge face and the leading edges gripped and extracted.

It will be seen that if there are carbon papers in a stack and if a wedge-shaped stabber-separator is used for penetration to segregate the lift, the carbon may smudge the paper because of the stabber impact and extensive area of contact. If there are self-supporting cardboard covers in the stack, and if the run permits the covers to project beyond the sheets, a vacuum cup separator may be used as in US. Pat. No. 3,155,244 to Rogers on Nov. 3, l964, there being no segregation problem because segregation and sheet count is predetermined by the projecting covers.

Similarly, as disclosed in US. Pat. No. 3,391,806 to Geis on July 9, 1968, air can be used to fluff out the endmost sheets in an end feed magazine to permit automatic count, whereupon a divider or separator can hold back the stack while grippers remove the counted lift. Such an apparatus would be impractical on a bottom feed magazine because the sheets would fall out when 2 the end plate was pivoted, and would blow out when air was applied. 3

SUMMARY OF THIS INVENTION In this invention a sheet magazine is provided with a hinged plate extending along the leading edges of the stack and the plate supports a lift thickness adjusting block having a sharp-pointed, small-diameter needle facing toward the front of the stack. The block is rectilinearly reciprocable relative to the plate so that, with the plate supporting the leading edges in the plane of the sheets; the needle may pierce into the leading edges of the stack, in parallelism with that plane, to segregate a predetermined number of sheets without visible nicking of the edges; smudging of the carbon or buckling efiect. Upon such needle-like segregation, a separate pressure clamp pivots against the leading edges of the next successive lift to retain the same, whereupon the plate pivots away from the stack with the needle and its lift to form a separation gap into which separate hold back fingers may enter. The needle and block then retract outwardly to release the lift and .to move out of thelift feed path so that gripper jaws may extract the lift from under the stack held back by both the pressure clamp and the hold back fingers.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a front elevation of the apparatus of the invention.

FIG. 2 is aside elevation.

FIG. 3 is a bottom plan view of the apparatus shown in FIG. 1. I

FIG. 4 is an enlarged perspective view from inside the magazine looking towards the gateway end thereof.

FIGS. 5, 6, 7, 8 and 9 are diagrammatic side elevations, with parts broken away of the cycle of operations of the apparatus.

DESCRIPTION OF A PREREPAID EMBODIMENT The apparatus of the invention may be used on any sheet treatment machine, for feeding lifts individually and successively onto the paper line of the machine, which may be defined by conveyor rolls, belts or aprons or registration lug chains, for advancing the lifts from station to station or zone to zone for treatment.

Exemplary of such machines is the machine disclosed in the above mentioned Malarnood US. Pat. No. 3,327,873 and the magazine feed of this invention could be substituted for the magazine shown in that patent, to segregate and separate the bottommost lifts for extraction by the reciprocating gripper jaws of such machines.

Only the gripper jaws and magazine portion of the feed section of the machine are shown herein, since the invention lies therein and the remainder of the machine is well known in the art.

The invention could probably be applied to an end feed magazine but, with the limp sheets for which the invention is especially useful, it is more practical and preferable to provide a bottom feed magazine 20 so that the stack 21 of limp, flexible sheets 22 is firmly supported on bottom 23 and the limp sheets have no tendency to buckle or collapse. The magazine 20 includes a fixed side wall 24 and a movable side wall 25,

slidably adjustable by set screw blocks 26 and 27 in slots 28 and 29, and a similar upstanding rear wall 32 slidably adjustable by set screw blocks 33 and 34 in slots 35 and 36 (FIG. 3).

Suitable side frame posts 37 and 38 extend upwardly on each side of bottom 23, there being a cross bar 39 extending between the posts and an upper cross shaft 41 journalled in the posts.

The stack 21 may include a selection of various sheets, all usually identical in dimensions, but some being limp as at 22, some being self-supporting to form covers as at 42 and some being carbon papers as at 43, depending on the particular run to be treated.

LIFI SEGREGATION MEANS stabbing on an arcuate path so that no visible nicking of the leading edges and no carbon smudging of the leading portions of the sheets will occur. Segregation means 44 therefore comprises an acicular surface in the form of a sharp-pointed, small-diameter needle 45, similar to a phonograph needle, mounted in front of the leading edges 46 of the sheets in stack 21 and facing toward the same in parallelism with the plane of the sheets 22 and with the plane of bottom 23. Needle, or segregator pin, 45 is fixed to a lift thickness adjusting block 47 which upstands in front of the leading edges of the bottommost lift 48 in the stack 21 and which is mounted on a segregator block 49 so that block 47 may be vertically adjusted in a slot by a, set screw 52 to segregate a predetermined number of sheets on a lift.

As best shown in FIG. 3, segregator block 49, thickness block 47, and needle 45 are reciprocable, rectilinearly by the pins 53 and 54 which are received in a pair of oblique tracks 55 and 56 in a two-track cam 57 which is reciprocated laterally by the air piston 58 and cylinder 59. when the piston 58 and two track cam 57 are at the in position in cylinder 59, the segregator assembly including needle 45 is in its outer or retracted position, and when in the out position, the segregator assembly including needle 45 is in its inner or advanced position with the needle 45 pierced into the leading edges of the stack to segregate a lift. The needle 45 may enter the edge of a cardboard cover, but not deep enough to cause marking or damage when lift is segregated. It normally enters between two adjacent, superposed sheets and whether of carbon or not, any smudge line is visibly difiicult to detect. The small diameter of the pin not only permits clean entry in a straight line between sheets, but also results in more accurate count of sheets or thickness of the lifts and avoids the possible ply splitting of cardboard caused by a large stabber travelling on an arc.

LIFT SEPARATOR MEANS The lift separator means 61 is also mechanical and includes means to move the needle 45 away from the stack 21 to separate, bow, bend or fold the leading edges 46 of each successive individual, bottommost lift 48 into the path of the reciprocating gripper jaws 62 and 63 (FIG. 9) for withdrawal from under the stack 21. Preferably, lift separator means 61 is a bottom plate, or support 64, hinged at 65 to the forward edge 66 of magazine bottom 23 and normally spring biased by coil spring 67 into a position in extension of the plane of bottom 23 underthe leading edges of the sheets in the stack. The segregation assembly including the needle 45, thickness block 47, segregator block 49 and air actuated cylinder 59 for cam track 57 are all mounted on the pivotable plate 64 so that when the needle 45 has penetrated the stack, as in FIG. 6, and the bottom plate 64 is moved downwardly to its first angular position 68, the separation gap 69 is formed. The plate 64 is then moved to the second angular position 71 in FIG. 8. The gripper jaws now enter the clamp onto the lower lift of paper. Now the segregator assembly moves outward to retract needle 45 and release the leading edges 46, and cam 72 lowers plate 64 to a third position to make clearance for the lift being extracted (FIG. 9). 1

The actuating mechanism for pivoting plate 64 includes the plate cam 72 (FIG. 2) on shaft 73, and shaft 73 being driven by connection with the drive of the basic machine on which the magazine 20 is mounted. Carn 72 is a three step cam which allows spring 67 to raise the plate to normal position shown in FIG. 5 and as the cycle progresses, cam 72 lowers plate 64 to second position 68 at about of the 360 cycle and then lowers plate 64 to third position 71 at about of the 360 cycle to clear the lift. The grippers 62 and 63 start to extract the lift at about of the 360 cycle. The needle cam 74 is mounted on the basic machine (FIG. 3) and synchronized with the drive thereof to actuate a follower arm 75 of a switch 76 which controls a solenioid actuated four-way air valve 77, the valve 77 controlling the operation of air cylinder 59 to advance and retract the segregator block 49 and needle 45 in accordance with the treatment operation being accomplished on the machine.

PRESSURE CLAMP MEANS The lift separation means 61 preferably includes a lever 81 pivoted at 82 to cross bar 39 and having a bifurcated lower end 83 which straddles adjusting block 47, without touching the block, and which has a forward face 84 for frictionally engaging the leading edges 46 of the next successive bottommost lift 85, but tapers away from the leading edges of the remainder of stack 21 as at 86. The upper end of lever, or arm, 81 engages a cam 87 fast to cam shaft 41, the shaft 41 having a sprocket 88 connected by chain 89 to a sprocket 91 on the cam shaft 73. Thus when the needle 45 penetrates the stack and then moves away therefrom with the edges of the sheets caught thereunder, the forward face 84 of arm 81 presses against the leading edges of the next set of sheets and tapers slightly thereunder to retain them in position as the separation gap 69' is created. Unlike the devices of the prior art, the member 81 is independently actuated and not part of the stabber or gripper.

HOLD BACK FINGER MEANS The lift separation means 61 preferably also includes a pair of hold back arms or levers 92 and 93, each pivoted at 94 to cross bar 39 and each having a relatively blunt, inturned hold back finger 95 or 96 for entering the separation gap 69 after it is formed by the downward movement of needle 45. The hold back members 92 and 93 each include an upper end 97 or 98 engaged by one of the cams 99 or 100 on cam shaft 41 and thereby synchronized with the basic machine through shaft 73.

The hold back members 92 and 93 and the pressure clamp member 81 each include threaded means 102 for raising or lowering the parts thereof in accordance with the thickness of lift desired to be fed as ascertained by the lift thickness adjustment block, 47

Lift segregation means 44 may include stack compression means 103 consisting of a pile riser 104 fixed by a screw 105 to the center of the bottom plate under the leading edges of the sheets to raise the lowermost sheets centrally a predetermined amount and thereby compensate for any inherent bow, especially in the cardboards (FIG. 4).

The magazine 20 does not have the type gateway used in sheet feeders for non-limp sheets, which pass only one thickness of sheet at a time because the sheets 22 are limp and must be extracted rather than ejected. Moreover, the magazine includes a pair of adjustable front wall elements 108 and 109 which depend from cross bar 39 down to a spaced distance from hinged plate 64 to define an opening 110 therebetween, which is in the same position as a gateway although not serving that function. A leaf spring 112 is fixed to each element 108 or 109 to guide the trailing end of each lift as the lift is extracted (FIG. 4) from the gateway end 110 of the magazine.

As shown in FIG. 3, a coil spring 120 in a plunger horsing 121, which actuates a plunger 122, and has compression adjusting set screw 123, may be used in place of, or to supplement, spring 67 as a return spring for plate 64. Preferably also the front wall elements 108 and 109 each include air emission slots 124 or 125, supplied with air under pressure from a mill pressure source by air conduits 126 or 127. The air jets are controlled for intermittent operation to direct pressurized air into the gap 69, as the gripper jaws enter the gap and continue to direct air into the gap during retraction of the grippers with each bottommost lift. An air cushion, bearing or separator is thus provided to prevent the bottom lift from frictionally withdrawing the next successive sheet with it, the air is required only when unusually light and flimsy sheets are being fed or when the paper has a high friction surface. It is also used to prevent carbon smudging as the sheets slide against each other during withdrawal.

What is claimed is:

1. In apparatus for feeding lifts of flexible sheets individually and successively from a stack of such sheets, said apparatus being of the type having a bottom feed magazine with a gateway and gripper jaws arranged to grip the leading edges of each successive separated lift and extract the same from under said stack the combination of:

mechanical lift segregation means including a sharppointed, small-diameter, segregation needle mounted in front of said magazine at a predetermined height above said bottom and mechanism for reciprocating said needle rectilinearly, in parallelism with the plane of the sheets to pierce between superposed sheets without visible damage thereto for segregating a predetermined number of said sheets as a lift; and

mechanical lift separation means, including a hinged bottom plate on said magazine, extending under the leading edges of the sheets therein, said plate supporting said' needle for reciprocation relative thereto and including mechanism for pivoting said plate, needle and the leading edges of said lift segregated thereunder downwardly to form a separation gap and to permit said gripper jaws to engage and extract the same.

2. Apparatus as specified in claim 1, plus:

at least one pressure clamp member mounted in front of said magazine to move independently of said needle, said member having a face adapted to bear against the leading edges of the next successive lift in said stack to frictionally restrain the same during segregation of the bottommost lift by said needle; and

mechanism for moving said member toward and I away from said stack.

3. Apparatus as specified in claim 1, plus:

at least one hold back member mounted in front of said magazine to move independently of said needle, said member having a hold back finger adapted to enter the gap created by said lift segregation means to hold back the leading edges of the next successive lift in said stack during segregation, separation and extraction of the bottommost lift therein; and

mechanism for moving said member toward and away from said stack.

4. Apparatus as specified in claim 1, plus:

pressure clamp means mounted on said magazine to move toward and away from the leading edges of each bottommost lift in said stack and frictionally clamp the same against feeding during said separation of the bottommost lift therein;

hold back finger means mounted on said magazine to move toward and away from the leading edges of said stack and enter the gap created during segregation by said needle to restrain and support the same against feeding during said separation of the bottommost lift therein; and

mechanism for moving said clamp means and said finger means independently of said segregation and separation means, but in synchronization therewith.

5. Apparatus as specified in claim 1, plus:

lift riser means on the center of the hinged bottom plate of said magazine for raising the sheets on the bottommost lift therein above the level of said bottom plate to compensate for any bow therein.

6. In apparatus for feeding lifts of flexible sheets individually and successively from a stack of such sheets said apparatus including a magazine for supporting a stack of said sheets with said sheets continually urged toward one end thereof and including a pair of gripper jaws movable to grip the separated leading edges of each successive endmost lift, and pull the lift out of said magazine, the combination of mechanical lift segregation means including at least one sharp pointed, small-diameter needle and reciprocation mechanism to pierce said needle into said stack at a predetermined distance from said end in a direction substantially parallel to the plane of the sheets for segregating a predetermined number of sheets without visibly damaging the same;

mechanical lift separation means, operably connected to said lift segregation means, for moving said needle, while so pierced into said stack, in a direction to separate the leading edges of the sheets segregated thereby away from said stack and to form a gap therebetween; and

hold back finger means, independent of said segregation and separation means for preventing separation and feed of the remaining sheets in said stack.

7. Apparatus as specified in claim 6, wherein:

said magazine is of the bottom feed type and includes a hinged bottom plate under the leading edges of said sheets normally supporting the same in a horizontal plane; and

said needle is fixed on a block upstanding from the front edge of said plate, and said block is reciprocable relative to said plate;

whereby downward pivoting of said plate moves said needle downwardly to separate the leading edges of the sheets segregated by said needle away from said stack. r

' 8. Apparatus as specified in claim 6, wherein:

said magazine includes a pivoted bottom plate, said needle is mounted to move downwardly with said plate and said lift separation means pivots said plate and needle downwardly to create a gap permitting entrance of said hold back fingers and then retracts said needle outwardly to a position out of the feed path of said lift for permitting extraction thereof by said gripper jaws.

9. In apparatus for feeding lifts of limp, flexible sheets individually and successively from a stack of said sheets supported on the bottom of a magazine, said apparatus being of the type having a pair of gripper jaws adapted to grip the leading edges of each bottommost lift separated from said stack and to pull said lift out from under said stack; the combination of a hinged bottom plate extending under the leading edge portions of the sheets in said stack and supporting said portions in the plane of said sheets, said support being pivoted to said magazine bottom;

separation mechanism for pivoting said plate downwardly to permit said leading edge portions to bend downwardly away from said stack;

a sharp segregation needle mounted on said plate at a predetermined height thereabove; and

segregation mechanism for reciprocating said needle to pierce between the leading edge portions of the sheets in said stack, in parallelism with the plane thereof, to segregate a predetermined number thereof;

whereby said segregation by said needle creates no visible damage .to said sheets.

10. Sheet feeding apparatus of the type including a magazine for supporting a stack of intermixed limp and self-supporting sheets and grippers for gripping and extracting lifts of said sheets individually and successively from the gateway end of said magazine, said apparatus comprising:

a support hinge-pivoted at the gateway end of said magazine, said support being normally in a plane parallel with the plane of the sheets therein but being pivotable out of said plane; a a sharp-pointed, s -d1arneter needle mounted on the free end of said support to reciprocate in a plane parallel to the plane thereof for piercing between adjacent sheets of said stack, at a predetermined distance from the plane of said plate to segregate a predetermined number thereof intoalifl; and v mechanism for piercing said needle into said stack, pivoting said plate and needle away from said stack to separate said lift and form a separation gap and then to retract said needle to permit said lift to be extracted from said gateway end by said pp 

1. In apparatus for feeding lifts of flexible sheets individually and successively from a stack of such sheets, said apparatus being of the type having a bottom feed magazine with a gateway and gripper jaws arranged to grip the leading edges of each successive separated lift and extract the same from under said stack the combination of: mechanical lift segregation means including a sharp-pointed, small-diameter, segregation needle mounted in front of said magazine at a predetermined height above said bottom and mechanism for reciprocating said needle rectilinearly, in parallelism with the plane of the sheets to pierce between superposed sheets without visible damage thereto for segregating a predetermined number of said sheets as a lift; and mechanical lift separation means, including a hinged bottom plate on said magazine, extending under the leading edges of the sheets therein, said plate supporting said needle for reciprocation relative thereto and including mechanism for pivoting said plate, needle and the leading edges of said lift segregated thereunder downwardly to form a separation gap and to permit said gripper jaws to engage and extract the same.
 2. Apparatus as specified in claim 1, plus: at least one pressure clamp member mounted in front of said magazine to move independently of said needle, said member having a face adapted to bear against the leading edges of the next successive lift in said stack to frictionally restrain the same during segregation of the bottommost lift by said needle; and mechanism for moving said member toward and away from said stack.
 3. Apparatus as specified in claim 1, plus: at least one hold back member mounted in front of said magazine to move independently of said needle, said member having a hold back finger adapted to enter the gap created by said lift segregation means to hold back the leading edges of the next successive lift in said stack during segregation, separation and extraction of the bottommost lift therein; and mechanism for moving said member toward and away from said stack.
 4. Apparatus as specified in claim 1, plus: pressure clamp means mounted on said magazine to move toward and away from the leading edges of each bottommost lift in said stack and frictionally clamp the same against feeding during said separation of the bottommost lift therein; hold back finger means mounted on said magazine to move toward and away from the leading edges of said stack and enter the gap created during segregation by said needle to restrain and support the same against feeding during said separation of the bottommost lift therein; and mechanism for moving said clamp means and said finger means independently of said segregation and separation means, but in synchronization therewith.
 5. Apparatus as specified in claim 1, plus: lift riser means on the center of the hinged bottom plate of said magazine for raising the sheets on the bottommost lift therein above the level of said bottom plate to compensate for any bow therein.
 6. In apparatus for feeding lifts of flexible sheets individually and successively from a stack of such sheets said apparatus including a magazine for supporting a stack of said sheets with said sheets continually urged toward one end thereof and including a pair of gripper jaws movable to grip the separated leading edges of each successive endmost lift, and pull the lift out of said magazine, the combination of mechanical lift segregation means including at least one sharp pointed, small-diameter needle and reciprocation mechanism to pierce said needle into said stack at a predetermined distance from said end in a direction substantially parallel to the plane of the sheets for segregating a predetermined number of sheets without visibly damaging the same; mechanical lift separation means, operably connected to said Lift segregation means, for moving said needle, while so pierced into said stack, in a direction to separate the leading edges of the sheets segregated thereby away from said stack and to form a gap therebetween; and hold back finger means, independent of said segregation and separation means for preventing separation and feed of the remaining sheets in said stack.
 7. Apparatus as specified in claim 6, wherein: said magazine is of the bottom feed type and includes a hinged bottom plate under the leading edges of said sheets normally supporting the same in a horizontal plane; and said needle is fixed on a block upstanding from the front edge of said plate, and said block is reciprocable relative to said plate; whereby downward pivoting of said plate moves said needle downwardly to separate the leading edges of the sheets segregated by said needle away from said stack.
 8. Apparatus as specified in claim 6, wherein: said magazine includes a pivoted bottom plate, said needle is mounted to move downwardly with said plate and said lift separation means pivots said plate and needle downwardly to create a gap permitting entrance of said hold back fingers and then retracts said needle outwardly to a position out of the feed path of said lift for permitting extraction thereof by said gripper jaws.
 9. In apparatus for feeding lifts of limp, flexible sheets individually and successively from a stack of said sheets supported on the bottom of a magazine, said apparatus being of the type having a pair of gripper jaws adapted to grip the leading edges of each bottommost lift separated from said stack and to pull said lift out from under said stack; the combination of a hinged bottom plate extending under the leading edge portions of the sheets in said stack and supporting said portions in the plane of said sheets, said support being pivoted to said magazine bottom; separation mechanism for pivoting said plate downwardly to permit said leading edge portions to bend downwardly away from said stack; a sharp segregation needle mounted on said plate at a predetermined height thereabove; and segregation mechanism for reciprocating said needle to pierce between the leading edge portions of the sheets in said stack, in parallelism with the plane thereof, to segregate a predetermined number thereof; whereby said segregation by said needle creates no visible damage to said sheets.
 10. Sheet feeding apparatus of the type including a magazine for supporting a stack of intermixed limp and self-supporting sheets and grippers for gripping and extracting lifts of said sheets individually and successively from the gateway end of said magazine, said apparatus comprising: a support hinge-pivoted at the gateway end of said magazine, said support being normally in a plane parallel with the plane of the sheets therein but being pivotable out of said plane; a sharp-pointed, small-diameter needle mounted on the free end of said support to reciprocate in a plane parallel to the plane thereof for piercing between adjacent sheets of said stack, at a predetermined distance from the plane of said plate to segregate a predetermined number thereof into a ''''lift''''; and mechanism for piercing said needle into said stack, pivoting said plate and needle away from said stack to separate said lift and form a separation gap and then to retract said needle to permit said lift to be extracted from said gateway end by said grippers. 